Event Delegation

What architectural pattern does this implement?

const createObservableDelegate = (element, options = {}) => {
  const subscribers = new Set();
  element.addEventListener(options.event || 'click', e => {
    const target = e.target.closest(options.selector);
    if (!target || !element.contains(target)) return;
    subscribers.forEach(fn => fn(e, target));
  });
  return {
    subscribe: fn => subscribers.add(fn),
    unsubscribe: fn => subscribers.delete(fn)
  };
};

Command pattern
Observer pattern
This implements the Observer pattern combined with event delegation. It allows multiple subscribers to observe and react to delegated events without direct coupling. Benefits include: 1) Separation of concerns between event delegation and handling, 2) Dynamic addition/removal of handlers without touching delegation setup, 3) Support for multiple independent observers of the same events, 4) Clean subscription management interface, 5) Maintained delegation efficiency with multiple handlers. This pattern is particularly useful for building modular, loosely-coupled systems.
Factory pattern
Singleton pattern

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